what psi to run
Turbo Mini Forums

im not sure what to run my mini at
i think standard psi is 4 but not sure if i should leave it standard to run it higher

whats your thoughts

positives and negatives thanks

from looking around the build threads on here i've seen most people run 10-15 in a road car. People may intend to start lower but the temptation of a bleed valve is always there.

Main thing is to make sure the engine is capable of handling the boost you want to run.

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

What do you want the car for and how big is your wallet?

If its an everyday road car you don't need more than 10 psi in my opinion.

might be worth posting the spec of your engine.

I think the general rule is... As much as you can possibly run without destroying the engine.

In the 13's at last!.. Just

Go big or Go home... Go too Big and your going home!!

Not much help sorry I run about 8 to 10 psi on the roads and on the strip well you always want more!!

I have started posting on Instagram also my name on there is turbomk1golf

Nothing is impossible it just costs more and takes longer.

It depends

From a theoretic perspective you have a few options, each option being a compromise in itself with differing needs to the chain of components that make your engine perform in a balanced way.

Option 1: Low boost, quick spool up turbo (small), high CR to make for a very responsive engine that comes on boost quickly with limeted top end power....but still some added ooomph compared to a N/A engine.

Option 2: High boost, big CFM -laggy- turbo, lowered CR. This makes for a very strong top end performer, keeping inlet temps / detonation at bay becomes a very real issue, as is keeping your bottom end + transmission in 1 piece!

Option 3: something in the middle

What components do you have to work with and what is it you want? What turbo do you have, do you run intercooling, are you intending to 'build' an engine to spec or use bolt on -external- components, do you have straight cut drops and if not are you willing to invest in them? etc. etc.

It all depends what you want.

When me and him were building the Fastest Upside Down Skip in the World (Probably), we found it drove at it's best with an MG Metro cam and about 12psi of boost on a T3 turbo. It was fast, but not daft fast and had very good road manners with regards to torque steer etc. When we added more boost, bigger cam, better turbo etc etc it just became daft and not much use on the road.

build the engine as strong as you can afford, have it set up correctly dont go daft with the boost, and enjoy a nice quick 'cough' reliable mini

10psi makes a nice quick mini 15-20psi grip starts becoming an issue

the na mg cam is a very nice road cam, and a t3 gives the effect of alot of power because it all comes at once

Yes i moved to the darkside

Instagram @jdm_brett

hi thanks for the comments,
as for the engine i bought the car with it in it was newly built and only done around 500miles
its running no intercooler at the moment.
i have drop gears but would this help putting them in a standard turbo box? or use a straight cut box?

as for the engine all i know is ts a 1310, forged pistons, morespeed booster head, new water cooled turbo, duplex chain

ive had my plenum to run an intercooler but want to use the car and dont want headaches with high boost and problems down the line

the box is the weaker link rather than the drops, the std gear kit starts to cark it at about 130-150 hp.

you need to know the compression ratio really, but I'd guess its pretty low,

without an intercooler I'd stick to less than 10psi,

the box was rebuilt but standard turbo spec, so is it worth putting the drop gears in or try to get a s/c box?
how do you find the compression ratio?
so can i run hight than standard boost without an intercooler?